1. Field of the Invention
The present invention concerns a method of optical sampling. In particular the invention concerns a method of sampling beam power of a laser.
2. Discussion of Prior Art
It has proposed to sample beam power of a laser by deflecting a fraction of the light in the beam onto a detector by means of a glass window in the beam inclined at an angle to the axis of the beam. This has the disadvantage of causing a significant loss of power in the light transmitted through the window as well as introducing possible distortion into the beam path.
Another technique known in the prior art involves scanning a conducting wire across the laser beam as described in GB 2158942A. This technique is inefficient because light energy has to be converted into heat in the wire.